For which pair of function is (g*f)(a)=|a|-2 1. f(a)=a^2-4 and g(a)= sqaureroot a 2. f(a)= 1/2a-1 and g(a)=2a-2 3. f
Question
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Answers ( 2 )
Answer:
The correct pair is 3
Step-by-step explanation:
1.
[tex]f(a)=a^{2}-4 , g(a)=sqrt{a} gof(a)=g(a^{2} -4)=sqrt{a^{2}-4 } neq |a|-2[/tex]
2.
[tex]f(a)=frac{1}{2cdot a-1}, g(a)=2cdot a -2gof(a)=g(frac{1}{2cdot a-1} )=frac{2}{2cdot a-1}-2=frac{4-2cdot a}{2cdot a-1}neq|a|-2[/tex]
3.
[tex]f(a)=5+a^{2} , g(a)=sqrt{a-5} -2gof(a)=g(5+a^{2} )=sqrt{5+a^{2}-5 } -2=sqrt{a^{2} } -2=|a|-2[/tex]
4.
[tex]f(a)=3-3cdot a , g(a)=4cdot a-5gof(a)=g(3-3cdot a )=4(3-3cdot a)-5=7-12cdot aneq|a|-2[/tex]
Hence, the Option 3 is correct
None of the pairs will deliver (gxf)(a). If you intend (gu2218f)(a), then …
… selection 3 is appropriate.